In the description that follows reference is made to certain structures and methods, however, such references should not necessarily be construed as an admission that these structures and methods qualify as prior art under the applicable statutory provisions. Applicants reserve the right to demonstrate that any of the referenced subject matter does not constitute prior art.
Nicotine extraction from tobacco using organic solvents has been disclosed by U.S. Pat. Nos. 3,096,773; 2,227,863; 2,128,043; 2,048,624; 1,196,184 and 678,362. Supercritical solvent extraction of nicotine from tobacco has been disclosed by U.S. Pat. No. 4,153,063 and commonly-owned U.S. Pat. Nos. 5,497,792 and 5,018,540.
Despite the developments to date, there is an interest in improved methods for extracting nicotine, flavor compounds and aroma compounds from tobacco. Furthermore, there is an interest in retaining the extracted nicotine and flavor/aroma compounds for subsequent tobacco processing and/or cigarette manufacture.